Rare aurochs-like traits and the breeds that have them

Some aurochs traits are easy to achieve in “breeding-back”, others are not. For example, it is really easy to breed for a basic aurochs-like colour as this trait is widespread among primitive aurochs-like breeds. Other traits are among the challenges for “breeding back”, also because they are very rare among living cattle. In order to achieve them in “breeding-back”, it is important to visualize where in which breeds these traits can be found. Otherwise the breeding result might not be that convincing in terms of aurochs-likeness. In this post, I mention only the primitive breeds that have some of the desired traits, not the “breeding-back” cattle which already might have some of the traits (f.e. the right body size in the case of Taurus cattle). 

 

Aurochs-like body size. This depends on what you consider an aurochs-like body size. As sexual dimorphism is a factor, I take the withers height of the bulls as a reference. European aurochs bulls varied from 160 to 200 cm or slightly more, therefore they are in the same size class as the wild yak. A number of breeds reach or surpass 160 cm. For example, some Sayaguesa and some Maremmana bulls (such as those acquired for the Auerrind project) reach 170 cm. Chianina and Maltese cattle reach 180 and maybe more in some cases. Modicana from Italy are also said to be 160 cm tall. I know of no confirmed cases, but Podolica and Boskarin might also surpass 160 cm. If one wants to breed for the larger end of the aurochs bull size spectrum, Chianina and Maltese are the only (taurine) options. 

 

Horns with an aurochs-like inwards curve. Horns curving strongly inwards as in the aurochs are found in some individuals of Maronesa, rarely also Sayaguesa. Very rarely, aurochs-like inwards-facing horns are found even in derived breeds such as Holstein (see van Vuure, 2005). Some Lidia also have inwards-curving horns, although their curvature is more two-dimensional compared to that in the aurochs. 

 

Short trunk as in the aurochs. This is a real challenge as this trait is not found in living taurine cattle, at least not in both sexes at the same time. Some Chianina, Maltese and Lidia bulls have an aurochs-like trunk length to leg length ratio, but never the cows. Only in primitive zebus (as outlined in the “challenges” post) have a trunk as short as in the aurochs in both sexes. 

 

Hump as large as in the aurochs. Found in some Lidia and also Corriente individuals. 

 

Elongated skull shape. Found in some Sayaguesa, Lidia, Maltese and Holstein cattle (and possibly others as well). 

 

Well-marked sexual dichromatism. Among the taurine breeds known to me, only Maronesa and the old type of Corsican cattle have a sexual dichromatism as strongly marked as in the aurochs. 

 

Aurochs-like body morphology. Only Lidia has a morphology (in some individuals at least) that looks plausible for a wild bovine, all other breeds have a domestic morphology - some more, others less. 

 

Udder size. The udder should not be visible from the side, as in a wild bovine. This the case in some Lidia and some primitive zebus. 

 

Looking at this list, it appears that for a breeding project that is ought to be successful, well-selected Maronesa, Sayaguesa, Lidia, Chianina/Maltese and primitive zebu are mandatory to achieve a phenotypic match with the aurochs that is as large as possible with domestic cattle. Taurus cattle already achieved many aurochs-like traits such as the right size (cows being 150-155 cm and bulls 155-170 cm tall at the withers), a satisfying sexual dichromatism, aurochs-like horn curvature at least in some cows and the right colour alleles are present (together with undesired alleles). One option would to start from anew with well-selected Maronesa, Sayaguesa, Lidia, Chianina/Maltese and primitive zebu and Watussi for the horn volume. Another option, that might be faster, is to take the best Taurus cattle and breed them for a more homogeneous phenotype, and then cautiously add what may be lacking in the herd, f.e. for the short trunk and small udder adding a F2 individual of (Taurus x primitive zebu) x Taurus that is well-selected, for the horn curvature (if not already achieved by selection with Taurus cattle alone) adding a suitable Maronesa individual, and for the morphology a Lidia individual plus a Watussi or Auerrind crossbreed for horn volume. With consequent breeding, the full potential aurochs-likeness that is achievable with domestic cattle could be seized. One must consider, however, that this would take at least 20 years.